Strip guiding apparatus

ABSTRACT

The disclosure of this invention relates to a strip entry guide for a rolling mill comprising two spindles associated with a top and bottom strip guiding assembly. Each spindle is adapted to support a number of guide bars to which are secured wooden elements that engage the opposite sides of a strip. This support is accomplished by separate nuts to which the bars are secured, each of which has a selected pitch thread that corresponds to a like thread formed on the spindles or an intermediate shaft for advancing the guide bars prescribed distances with respect to coordinated guide bars on the other side of the guide.

llnite atent 91 Volker et al.

[ 1 May 29, W73

[ STRIP GUIDING APPARATUS 3,406,553 10/1968 Gross et al ..72/25O X [75] Inventors: Karl-Heinz Volker; Dieter Brockow, I

both of Hilchenbach-Dahlbruch, Pr'mm '"P Germany Attorney-Henry C. Westtn [73] Assignee: Siemag Siegener Maschinenbau, 57 ABSTRACT G.m.b.H., Dusseldorf, Germany The disclosure of this invention relates to a strip entry Filed: 14, 1972 guide for a rolling mill comprising two spindles as- [211 App] NO; 234,556 sociated with a top and bottom strip guiding assembly. Each spindle is adapted to support a number of guide [30] Foreign Application Priority Data bars to which are secured wooden elements that engage the opposite sides of a strip. This support is ac- 17, 1971 Germany 21 12 753-7 complished by separate nuts to which the bars are secured, each of which has a selected pitch thread that [52] US. Cl ..72/250 corresponds to a like thread formed on the spindles or [51] Int. Cl. t ..B2lb 39/20 an intermediate shaft for advancing the guide bars [58] Field of Search ..72/250, 227 prescribed distances with respect to coordinated guide bars on the other side of the guide. [56] References Cited 5 Claims, 1 Drawing Figure UNITED STATES PATENTS 3,07l,032 1/1963 Teplitz ..72/250 2,962,917 12/1960 Drysdale ..72/25O X PATENTEB MAY 2 91973 W///// @7 ////4 J/////// M l STRIP GUIDING APPARATUS The invention relates to a strip entry guide for a rolling mill. Strip guides of this type have a number of upper and lower drag boards for both guiding the leading end of a strip supplied to roll stands, coilers or the like, and, after the end of the strip is released, the guides continue to retain the strip under the desired longitudinal tension by engagement of the boards with the end of the strip. To permit adaption of the guide to different strip widths, it is necessary to construct the boards so that they are adjustable and to adapt the distance between them to the appropriate width of the strip. To ensure uniform engagement of the strip and in the interest of achieving uniform tensioning of the strip, as well as of the boards, it is necessary for the aggregate width of the board surfaces to correspond to the width of the strip.

It is common practice in present strip guides to provide a number of wooden boards in which the width of the guide is increased by the insertion of additional boards and reduced by the removal of boards between end guide strips provided to retain the opposite edges of the passing strip. Such resetting for different strip widths has been found to be time-consuming and difficult to perform. The wooden boards are not only subject to substantial wear, but difficulties also occur in securing the boards to the frames of the guides and handling thereof is not without hazard and requires the full attention of the operators.

US. Pat. No. 3,071,032 which issued to A. Teplitz on Jan. 1, 1963 discloses a strip entry guide in which adjustment to be required guide width is performed by power-driven means. The upper, as well as the lower, operating board platens are provided with separate motors and two screw-threaded spindles with threads of opposite hands adapted to engage spindle nuts of the outermost boards. The boards disposed therebetween, when compressed and bearing upon each other, define the minimum width of the strip guide in which they are coupled to each other and to the outer press boards in a positive way in the manner of a scissors system so that, in driving apart the outer boards, the boards disposed therebetween traverse distances which are proportional to their means distances from the plane of symmetry of the strip guide. However, it has been found awkward and complex to control the separate drive mechanisms for the upper and lower platens when resetting to a different strip width. In this connection it has been found to be a disadvantage that oppositely disposed boards do not retain their direct opposite relationship if the traversing paths of the power driven means do not completely correspond, so that the tension on the strip is diminished and/or becomes asymmetrical. In addition to these limitations of the prior art, the positive guides acting within different planes of the upper and lower boards are found not to be able to withstand the rough service conditions and the severe exposure to dirt and abrasion.

The invention is based on the object of providing a strip guide, the guide bars for supporting the boards of which have power-driven adjusting means and in which the bars are positively adjusted to identical widths within two planes, the bars participating in the motion in proportion to their mean distances from the plane of symmetry of the guide and in which the mechanism for performing such motions is constructed so ruggedly as to be able to withstand the rough service conditions and the risk of dirt without calling for special maintenance.

The present invention more particularly provides a strip guide of the kind heretofore described including a screw-threaded spindle having screw-threaded portions, the number of which corresponds to that of edge bars or guide bars which are to be moved within the range of the guiding surface, the said bars being provided with spindle nuts which engage with the screwthreaded portions, the pitches of the screw threads being proportional to the mean distances between the coordinated edge bars or guide bars and the plane of symmetry of the guide and, furthermore, the outer diameters of the screw-threaded portions diminish from the inside to the outside at least to the core diameter of the preceding screw-threaded portion, the screwthreaded spindles being coupled through a vertical shaft by means of bevel gearing of which at least one bevel gear is adapted to slide axially by means of splining on the vertical shaft.

It is possible to eliminate the separate screw-threaded portions for the guide bars which may be disposed in the middle by providing an odd number of bars, the middle bars being in each case stationarily supported within both planes of the guide elements of the guide. A particularly space-saving embodiment may be obtained if screw-threaded portions are provided on the external circumference of spindle nuts constructed as hollow cylinders, surrounded by a further outer spindle nut and that the sum of the pitches of the internal and external screw threads with reference to one rotation of the spindle corresponds to the mean distance between coordinated guide bars and the plane of symme try of the guide. In this case the inner of the spindle nuts can be positively driven by an intermediate drive in order to provide movement for the particular coordinated guide bars associated with the aforementioned spindle nuts, as well as providing movement for the other guide bars by means of further spindle nuts when the screw-threaded spindles are driven.

Such an assembly may be achieved if a hollow shaft having a screw-threaded portion and extending over the spindle is connected with a spindle nut of an inner guide bar and is axially guided thereby, the hollow shaft being rotationally joined to the spindle and being surrounded by the spindle nut of an adjacent guide bar. In this case the bar movement will be the direct sum of both pitches since the rotation of the screw-threaded shaft and of the hollow shaft are necessarily the same.

One embodiment of the invention is explained hereinbelow by reference to the accompanying Drawing representing a vertical section. To indicate the two extreme positions of the guiding elements, the left-hand half section shows the boards in their converged state for guiding a minimum width strip, while in the righthand half section they are shown in the extreme divergent state for guiding a maximum strip width.

The Drawing shows a frame 1 to which a lower screw-threaded spindle 2 is rotatably supported and which may be driven by driving means, not shown, through chain sprockets 3 disposed on the spindle. A vertical shaft 5 is coupled through a bevel gear set 4 to the spindle 2 and entrains, through a bevel gear set 6, an upper screw-threaded spindle 7 which is rotatably supported in a guide frame 8. The vertical shaft 5 rotates the bevel gear set 6 through a spline section 9, but

yet permits vertical adjustment when the guide frame 8 is raised and lowered. Being driven by the same driving means, the screw-threaded spindles 2 and 7 perform identical motions. Guide bars 10 are arranged at identical mean distances between further guide bars 11, 12 and 13, all of which are disposed in the frames 1 and 8. The outer guide bars 13 of the frame 1 are also provided with strip edge guide strips or bars 14. The guide bars and edge guide bars are provided with exchangeable wear members, such as wooden guiding elements.

In the middle zone the screw spindles 2 and 7 are each provided with a first screw-threaded portion 15 and a further screw-threaded portion of the same diameter and the same pitch, but reversed hand, is symmetrically disposed relative to the first-mentioned portion. As noted before, the threads for effecting the cooperative movements of the bars are proportional to the mean or common distances between the coordinated pairs of bars and the plane of symmetry of the guide. On each side a spindle nut 16, coupled to the guide bar 11 and defining its movement, engages with the screwthreaded portion 15. If the pitch of the screw-threaded portion 15 is 3 mm, it follows that each rotation of the screw-threaded spindles 2 and 7 will displace the spindle nut 16 with the associated guide bar 3 mm in the axial direction of the spindle.

If desirable, a further screw-threaded portion of double pitch can be provided on the spindle for the next guide bar 12; however, in order to save space, separate members can be provided to overlap the traversing zone of the threaded portion. In this case and as shown in the drawing, the spindle nut 16 is associated with a cone 17 which extends over a collar of a hollow shaft 18 and, thus, rotatably supports the shaft while holding it so that it will move with the spindle nut 16. As shown in the illustrated position of the upper screw-threaded spindle 7, the hollow shaft is coupled to the spindle in both a rotational and longitudinal slidable manner by means of a key 19 and keyways 20. Rotation of the screw-threaded spindles 2 and 7, therefore, causes the hollow shafts 18 to be axially displaced with the spindle nuts 16 and rotated with the screw-threaded spindles. The outer surfaces of the hollow shafts 18 are provided with screw-threaded portions 21, also having a pitch of 3 mm and which are engaged by the spindle nuts 22 which, in turn, are fixedly joined to the guide bars 12. If the screw-threaded spindle is rotated through one revolution, the hollow shaft 18 will participate in this revolution and will also be axially displaced by 3 mm so that its over-all movement, and, accordingly, the axially parallel displacement of the guide bar 12, is defined by the sum of the individual displacements, which amounts to 6 mm.

A separate screw-threaded portion 23 having a pitch of 9 mmis provided for the guide bar 13 having the guide bar 14 so that the spindle nut 24 extending over the aforementioned screw-threaded portion displaces the guide bar 13 with the guide bar 14 in the axial direction by 9 mm for each revolution. The diameter of the screw-threaded portion 23 is made smaller than that of the screw-threaded portion 15 so that, during assembly, the spindle nut 16 may be easily slid over the aforementioned portion.

The following procdeure takes place during the traversing of the guide bars from the condition shown at the left of the drawing in the direction of the condition assumed at the right. If the screw-threaded spindle 2 is rotated through one revolution, the upper screwthreaded spindle 7 will be positively rotated through the same angle irrespective of the position or vertical motion of the guide frame 8. The middle guide bars 10, being disposed stationarily in the plane of symmetry of the guide, require no adjustment. Each of the guide bars 11 adjacent to the opposite sides of the bars 10 are displaced by one pitch length during this rotation, i.e., in the example given by 3 mm. The hollow shafts 18 participate in this axial displacement and, in addition, rotate an amount equal to the rotation of the spindle nuts 16 causing each spindle nut 22 to be displaced by the double distance in accordance with the double mean distance between each pair of lower and upper guide bars 12 which in the embodiment amounts to 6 mm in the case of one revolution for each bar 12. The guide bars 13 and the connected guide bars 14 have a triple distance from the plane of symmetry. The separate screw-threaded portion provided for the aforementioned guide bars imparts a triple movement, i.e., a movement of 9 mm for one revolution, for each bar 13.

The invention is not confined to the illustrated embodiment. For example, if there is no lack of space, it is possible for screw threads with spindle nuts associated therewith to be provided on the screw-threaded spindles for all guide bars, thus dispensing with the need for the separate hollow shafts. On the other hand, it is possible for several such hollow shafts to be provided and it is also possible to provide hollow shafts which extend over each other. The hollow shafts need not necessarily be driven by the shaft itself, but a separate shaft may, for example, be provided with sprockets and chains. The sum of the movements in this case is defined by the rotational speeds, no longer positively coupled, in conjunction with the appropriate screwthread pitches.

It is also not necessary to arrange the bevel gear transmissions so that the upper as well as the lower screw-threaded spindles are rotated through identical amounts. If, for example, the upper screw-threaded spindle is rotated one and a half times as rapidly as the lower spindle, upon the selection of a different transmission ratio for the same movement of the guide bars, the pitch of the screw-threaded portion of the upper screw-threaded spindle should be only two-thirds that of the corresponding screw-threaded portions of the lower screw-threaded spindle. Furthermore, it is not necessary to employ bevel gear transmissions for transmitting the motion. It is possible for worm gear transmissions to be provided, in particular, if sufficiently reliable vertical guiding is ensured in the spline section 9. In this case, the drive would act on the vertical shaft which would have to be provided with the worms while the screw-threaded spindles would be associated with the worm wheel.

The drawing represents a section through two superjacently disposed screw-threaded spindles. In practice and in order to avoid jamming within the guideways, it may be advantageous to provide a second group of such screw-threaded spindles which could be offset relative to the longitudinal orientation of the strip guide. Synchronism can also be ensured in this case if the two lower screw-threaded spindles are driven from the same drive and are coupled to each other, for example, by means of chains. The same can be achieved by coupling the vertical shaft 5. In all cases, positive symmetrical adjustment of the guide bars and edge guide bars of the frame, as well as of the guide frame, is ensured without special precautions so that the adjusting procedure is greatly simplified. Furthermore, the adjusting procedure is performed by means of rugged splines so that a long working life and long intervals between maintenance operations may be achieved.

in accordance with the provisions of the patent statutes, we have explained the principle and operation of our invention and have illustrated and described what we consider to represent the beat embodiment thereof.

We claim: 1. A strip guide for a rolling mill and the like comprismg:

upper and lower guide assemblies, each having a number of guide bars, at least some of which are movable, that make up guiding surfaces engageable with the opposite sides of the strip, at least one of the guide bars of each assembly forming a coordinated pair with another bar on the opposite side of a plane of symmetry of the guide of the same assembly, a separate spindle for each assembly having right and left-hand threads formed on their opposite ends, means for rotatably supporting said spindles, said threads of said spindles being made up of different threaded axial portions, the number of which portions corresponds to the number of movable guide bars of each assembly, each of said movable guide bars having nuts, at least some of which are arranged to engage with a different one of said threaded portions, and the pitches of said threaded portions being proportional to the mean distances between at least one of said coordinated pairs of guide bars and said plane of symmetry of the guide, and wherein the outer diameters of said threaded portions for at least one coordinated pair of bars diminish in a direction outward of said plane at least to the core diameter of the preceding threaded portion.

2. In a strip guide according to claim 1 including a shaft,

means for coupling said shaft to said spindles and means for supporting said coupling means in a manner to allow it to slide axially of said shaft, and means for rotating one of said spindles.

3. In a strip guide according to claim 1 wherein said guide bars for each assembly consist of an odd number and wherein said guide includes means for stationarily supporting the middle guide bars of each assembly.

4. In a strip guide according to claim 1 wherein threaded portions are provided on the external circumference of additional nuts for a coordinated pair of guide bars,

said additional nuts being constructed in hollow cylindrical form, and each arranged to be surrounded and thereby engaged by a difierent one of said other nuts,

the sum of the pitches of the internal and external threads of said additional and other engaging nuts with reference to one rotation of said spindle being proportional to the mean distance of said coordinated pair of bars associated with said other engaging nuts,

and wherein said additional nuts are coupled by intermediate driving means.

5. In a strip guide according to claim 1 including a hollow shaft for each spindle having a threaded portion and extending over a portion of its associated spindle,

means for connecting said shaft with a nut of a first guide bar in a manner that it is axially movable therewith,

means for connecting said shaft with said spindle so as to rotate together,

said shaft being arranged so as to be surrounded by a nut of a second guide bar.

Patent No. 3,735,62L D Mav 29, 97

Inventor) Karl -Heinz VVolkel, et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the cover sheet item "KarlHeinz Volker should read Karl Heinz Volkel Signed and sealed this 2nd day of April 197A,

(SEAL) Attesc:

EDWARD M .FLETCHER JR C MARSHALL DANN Attesting Officer Commissioner of Patents FORM PC4050 uscoMM-oc 60376-P69 & u.si GOVERNMENT PRINTING OFFICE l 989 0-366'33l. 

1. A strip guide for a rolling mill and the like comprising: upper and lower guide assemblies, each having a number of guide bars, at least some of which are movable, that maKe up guiding surfaces engageable with the opposite sides of the strip, at least one of the guide bars of each assembly forming a coordinated pair with another bar on the opposite side of a plane of symmetry of the guide of the same assembly, a separate spindle for each assembly having right and left-hand threads formed on their opposite ends, means for rotatably supporting said spindles, said threads of said spindles being made up of different threaded axial portions, the number of which portions corresponds to the number of movable guide bars of each assembly, each of said movable guide bars having nuts, at least some of which are arranged to engage with a different one of said threaded portions, and the pitches of said threaded portions being proportional to the mean distances between at least one of said coordinated pairs of guide bars and said plane of symmetry of the guide, and wherein the outer diameters of said threaded portions for at least one coordinated pair of bars diminish in a direction outward of said plane at least to the core diameter of the preceding threaded portion.
 2. In a strip guide according to claim 1 including a shaft, means for coupling said shaft to said spindles and means for supporting said coupling means in a manner to allow it to slide axially of said shaft, and means for rotating one of said spindles.
 3. In a strip guide according to claim 1 wherein said guide bars for each assembly consist of an odd number and wherein said guide includes means for stationarily supporting the middle guide bars of each assembly.
 4. In a strip guide according to claim 1 wherein threaded portions are provided on the external circumference of additional nuts for a coordinated pair of guide bars, said additional nuts being constructed in hollow cylindrical form, and each arranged to be surrounded and thereby engaged by a different one of said other nuts, the sum of the pitches of the internal and external threads of said additional and other engaging nuts with reference to one rotation of said spindle being proportional to the mean distance of said coordinated pair of bars associated with said other engaging nuts, and wherein said additional nuts are coupled by intermediate driving means.
 5. In a strip guide according to claim 1 including a hollow shaft for each spindle having a threaded portion and extending over a portion of its associated spindle, means for connecting said shaft with a nut of a first guide bar in a manner that it is axially movable therewith, means for connecting said shaft with said spindle so as to rotate together, said shaft being arranged so as to be surrounded by a nut of a second guide bar. 